Method of making prism-glass.



No. 827,484. PATBNTED JULY 31,v 1906.

F. L. WADSWORTH.

METHOD OP MAKING PRISM GLASS..

AIPLIOATION FILED JUNE 28. 1904.

2 SHEETS-SHEET 1.

PATENTED JULY 3l F. L. O.v WADSWRTH. METHOD OF MAKING PRISM GLASS APPLICATION FILED .TUBE 2B.

2 SHEETS-SHEET 2.

mvsuron WITNESSES UNITED sTaTEs PATENT onirica,

FRANK L. O. WADSWORTH, OF MORGANTOWN, WEST VIRGINIA, ASSIGNOR TO PRESSEQ PRISM PLATE GLASS COMPANY, OF NEW YORK, N. Y., A CORPORATION OF WEST YIRGrINlA.- r f METHOD. oF .MAKnNG PRISM-GLASS.

Patented July ai, 1906.

Application filed J' une 28, 1904, Serial No. 214,442.V

To all whom it may con/cern:

Be it known that I, FRANK L. O. WADs- WORTH, of Morgantown,`Monongalia county, West Virginia, have invented a new and useful Method of Making Prism-Glass, of which the followin is a full, clear, and exact description, re erence being had to the accompanying drawings, forming part of this specie iication, in which- Figure 1 is a side elevation, partly in section, of one form of apparatus which I may employ in carrymg'out my invention. Fig. Ia is a plan view of one of the guns I employ.

Fig. 2 4is a plan view ofllg. 1. Fig. 3 is a of the apparatus.

Fig. 4 is a lon itiidinal section showing a modified form c apparatus which I may emplloxy, and Fig 5'is a cross-section on the line ofFig. 4.

- In the manufacture of sheets of prism-glass where the prism pattern is impressed upon a rolled glass sheet difficulty has been eXperienced in making such sheets of considerable thickness.` When they arethick, the body of molten glass is very large and hot,- and w en the pressing-die is brought upon it the pattern-surface is apt to `be injured by the heat and the operation is delayed by the necessity which exists of waiting for a considerable time after each pressing operation in order to permit the die to cool.` It is also difficult to remove the sheet from the' table and from injury to the apparatus,

then impressing the die.A Moreover, the pattern produced in this manner is frequently defective, and owinv-to the thickness of the glass its surface will be different int emperature from the interior, and the glass is therefore apt to curl up' when placed in the'leer. Like dihiculties are encountered in the manufacture of figured sheets of other forms wherever it is attempted topress the pattern upon the surface of a thick body of glass. The method which I have invented overcomes these dilicultie's and makes it possible to carry on the manufacture of glass sheets quickly and without to anneal them without distortion, and to produce a perfect pattern.

In the practice rolling the thick sheet ina single mass and the pattern upon it I roll it in two or more layers-that is to say, I irst l simply rollin skilled in the art.

of my invention mstead 0fspread out upon the rolling-table a glass sheet of ordinary thickness, such as can be easily managed, and then I roll a second, and, if desired, va third sheet, and finally impress the pattern up on the glass. The interval or intervalsbetween the formation of the sheets allows the successive layers of glass to cool somewhat, so that when the pattern is impressed the sheet is not unduly hot'and the operation therefore does not result in injury to the die, nor does it make it difficult to form the pattern or to remove the sheet from the table. The cooling ofthe lirst layer of glass before the completion fthe second also equalizes the temperature of the opposite surfaces, and when placed in the leer they will anneal with-l out curlingup.

In addition to merated the pressing operation as herein described produces a further beneficial effect of compressingthe two sheets of glass together. with any interposed material that may be placedbetween them into a single homogeneous' article of more uniform density and greater transparency than' can be secured by one sheet on top 'of another.

On account o this fact the invention may-be practiced even when the pressing-die hasfno pattern formed upon it-and where the pressure is employed merely to render more compact a compound sheet having plain surfaces. The manufacture can be conducted rapidly, and my invention possesses many other advantages which will be appreciated by those The vmethod above described may bepracticed in apparatus of many Jforms.` The apparatus which I have shown in the drawings as preferable is constructed substantially as shown and described in the patent of Ripley and Wadsworth, No. 661,024, dated October 30,- 1900, and I will now describe it. The machine consists ofa main frame, preferably portable, wheels 3, on which it can be moved on suitable tracks vin front of the annealing-oven. This main frame is built up of a base-plate 4,- which sup orts four heavy steel columns 5,

y'and of a eavy'boX-shaped casting1 6, supthe advantages already enu.

and mounted, as shown, on

y platen 9.

,spreading-table or platen 9 rolls. tergof the .box-shaped casting between the mounted small rollers 8, on which a movable In the cento this end suitfWith the piston 14, moving in a cylinder 15,.

. mounted on the base-plate 4.

tica 'separation between the roll and the ta- .Above the table 10 and also supported by the side columns aremounted tw'o bars 16 1,6, the ends' of which project forward over the front end of the machineand are slotted, as at 17, to receive boxes which areadjustable vertically with reference to the platen by means of a lever 18, engaging the bearings of the'roller 19 and adapted to move em vertically in order lto increase the verr ble when the second layer of the sheetis to`be r rolled.

machine. `The frame .20 l springs 24 is held down Above the bars 16 and'slidingfreely on the side column is a frame 20, having at opposite Sides two hangers v21, in which are pivoted the'trunnions of a die-plate 22, which serve as'thesupport for the up er die 23 of the by the action vof against adjustable stops on the columns 5. To hold the upper die 23 in proper relative position to the lframe 20, screw-eyebolts 25 are provided,which are pivted at the lower ends to bosses on 'the die-plate 22 and are clamped at the'upper screw ends to the' frame 20 by means of nuts 2,6`and washers' 27, engaging on opposite sides of theslotted '45 [the die-plate 22 by lugs 28, projecting from upper die 23 is held to 4 means ofbolts or setscrewsjand has at its sides two knife-edge cutters 29 29, projecting somewhatbelow the the frame 20. The

'lower'surfaces of the die, and also two projectingwedge-shaped pieces'3() 30, the object o which Will be explained hereinafter.

The platen 9 has a smooth under surface which rolls upon the surface of the, rollers 8 8. Itv 'has side strips 31', which may be attached `y means of screws 32, 'slots in the said strips and allow of a certain which pass i through vertical adjustment of the latter, so Ithat'the top edges of these'strips may be brought just in contact with the surface of the'roller 19.

' theseJ strips are beveled, as shown, and are l Atthe'ends of thetable are strips 33 33, the

top 'surfacesy of which' are flush with the surface of Athe platen 9. The e inner edges of normally held in close contact with the edge of the recess inthe table by means of springs 34,

:roller 19 at the' same tapes 36 are vwrapped -table 10 may be and at the ends of the strips are pins 35, which 'project through slots 'in the side plates 31.

In order to move the platen Qunder the speed at'whichthe surface of the latter revolves, two steel cords or around the ends of the roller, pass over idle pulleys 37 on the frame of the machine, and backward to across-bar 38, which slides on the main frame of themachine, and has at the center a pin 39, which hooks into the end of the platen 9. To keep the cords 36 taut, a second cord 40 is continued back to the end of the frame and there attached to a weight 41, as shown, or to` a spring or some equivalent device. Y The central table 10 is supported when in its lower position on the roller-bearing 42 of the tripod 12 and on the adjustable bearings 43, (shown as screws,) set normally at such a height that the top surface of said table is on a line with the top surface of the rollers 8 8, already described. Through the side ribs 44 of the said table. are holes through which pass loosely the ends of journals or shafts 45 of rollers 46.- The ends of the shafts 45 rest whenthe table is down in V-shaped notches 47 in two bars 48, which-are adjusted to such a height by means of screws 49'that the top surfaces of the rollers 46 are then just'above the surface of the table 10. When, therefore, 'the table is in this position and the platen'9 is moved forward uponpit, it rolls easily upon these rollers; but as soonfasthe table'l'O is lifted above this position, carrying the rollers 46 with it, the endsofthe shafts 45 are lifted out4 of the notches in the bars48," allowing the rollers to descend slightly and the platen 9' to settle down intocontact with the table 10, it being heldin proper relation thereto by means of the beveled side flanges 11 and also small bevel projections 50, running across the lower surface of ,the table at right angles to theseside pieces.v Any other suitable steadying devices may be used.l Throughy the lower plates of the boxshaped casting 6 projects a screw50, which serves asA a stoputo hold the tripod-headand its attached table 10 at the properheight.

Connected with the cylinder 15 is a pipe v5 1, communicatingwith the valve-casing 52, by

IOO

meansof'which airv can be admitted'or alvlowed to escape from the cylinder 15 by manipulating the 'valve by means ofthe valvelever 53.; l i

4 'I he roll .19, carrying with itin rotationvthe platen 9, is'rotated by means of a crank 54 or equivalent device in the case of a small machine or by means of an electric or other, mo-

tor geared thereto in thecase of a larger one.

In operating the machine I proceed as folj lows; I first adjust the height ef roller 19 -by shifting itsI bearings, by means of k'thelvlever 18, to such a distance fromA the surface of the platen 9 as will produce the iirst sheet of glass ofthe requiredthickness, the side strips ',scribed. :The platen 9 is run back to a positheplaten between the guns next 'to the m' on the table being adjusted to such a height that they are just in contact with the lower surface of the roller, as already detion in which. it is entirely lfrom under the roller: 19 anda pair of gunsA of the usual 'constructionl placed in -front of the roller. Molten" glass is then poured upon the ,end of roller, as in making ordinary plate-glass;

l ',lhe'roller v'19 isl then caused to spread out the glass deposited thereon into Va sheet of the re- -q ed-thicknes's, andthe operation is con- -itiiiueduntil the platenl has' assed entirely fiinder the'roller. y The pair o guns A is then iijgimoved, the lever' 18 depressed, so as to raisefthe roller slightly, and the platen then -'xl{etra'otedto lits original position by means of ;the; .weight ldi. second pair' of guns A of fsuch'- wldthasto rest'.` directly o n the side 'stri s,is then ,placed'in position, and another bo4 y ofinolten glass is poured between them glassfirst rolled; The roller is] again caused tds'pread outthe ksecond body of lass in a layer u onthe layer iirst formed, t us mak- `ing'as eet---oi'increased thickness'. At the. ev d ofthe Telling of the second la er of lass feplaten .reskupon the top of t e tab e 'iirjproper position for-.the V-sha ed projectiosfon the latter tosengage wit the correspending grooves in t" e laten. The valvelever 53 is 'now depresse to Vadmit air to the cylinder j and raise the head and the attached table toward the the glass-into the 'cavities of the `die and ,brings thel glass into contact with every portion 'of thesaid cavities,- thus molding, shaping, 'and finishing the glass into prism form. Inl order that there may be intimate contact between v.the die and the glass within the cavities, l vent each of the cavities by causing it' to communicate with the atmosphere.

In I the risul-forming 4cavities A'extend across the ace of the die in parallel position, 'the en d of each vcavity is formed, with a h ole or is' left open, thus providing the needed air-vent. At the same time with the descent' of the u per die the wedge-shaped pieces engage t e pins 35 of the strips S3-as the table rises and forces the latter strips -outward,`

leaving openings ipfn which the cutters 29 descend, and indent 'or shear 0H the rough 'ends of the glass. -After the glass hasremained in contact with 'the upper die long enough to set the valve-lever 53 is released, allowing the air to escape from the cylinder 15 and the table' to descend to its lowest position. The stop 54 is then turned and the hook 39 disengaged, so as to allow the platen e 9 to be drawn through to the end of the machine 'opplcite that at which itis entered; The mac e is so placed that the glass sheet directly on the sheet of die 23; This forces die whichfjl have shown, wherekthe l63, carrying the glass,

rpoured upon the to yble sheet o'glass is drawn upon a' 'faces'of v,the glass.

may then be removed* directly from this 65 table by 'suitable means and placed in the annealing-oven. The platen 9 is then run back to its first position and is ready for the repetition of the operation.

In Figs. `3 and 4 I show a modified con- -struction of my apparatus, in which l illustrate other means by which the combined glass sheet may be rolled and manipulated. In this case the table 55 is provided with a gun A ol' usual construction, and the table 'is adapted to be pulled under the roll56 by a rope 57, which winds upon a drum 58,'the

latter bein driven -by sprocket mechanism from the ro l 56. i By means of this chain the table is drawn under the roll and carries the sheet into a rotating cylindrical frame 59, in which it is'supp'orted by rollers 60 and is held in placeby flanges- 6l onthe frame engaging tonges 62 on thetable. When the table 1s wit 'n the frame, a second table 63, which is alsosupported within the frame by eccentrics 64, is lowered u on the glass by turnin the eccentrics. The frame is then rotate on its longitudinal axis through' one' hundred and eighty degrees, so as to reverse the positions of the tables 55 and 63 and to bring the'table 55 .uppermost and the table 63 directly above the rollers 66.. The table is then lowered 'upon the rollers-66 by reversing the eccentrics, the table 55I being meanwhile supported by the and ilanges 61, and the table 63 is then drawn, cylindrical frame 59 and under a second roller 68. A second ladle of glass is then of the rst'sheet in viront of the second ro l, and the motion being continued thetable is drawn under the second roll and the second sheet of glass is rolled down upon the irst. The motion being head 69, which is vertically moya le in a frame carrying 'a pressing-die 70, backed by springs 71, the motive powerbeing supplied by a cylinder .-72 and piston 73, connected with the head by levers 74 and 75i When the piston 73 `s projected, the pressing-head 69 is raised with the table 63,'thus`br1nging the glass'into contact with the pressing-die further continued,the table with'the douressingby means of a chain 67 out ofthe IOO IIC

7 O, pressing the twov sheets of glass into intil mate contact and impressing. the pattern.

of thedie 70 and table 63 upon the opposite The head 69 may 'then be lowered, the table 63 pulled forward upon rollers 76, where the'glass may be removed,

and the ytable thenpushed back within ,the cylindrical frame'59, the latter turned back one hundred and eighty table 55 pushed .to the rear 'o the roll 56'-,to receive :another'icharge' o gla'lss.

. The inversion of the -jirst layer-ofthe com- Adegrees andthev ,p oundsh'eet"accomplishes a specific purpose y C iff s of great advantage, since it makes possible I the production of a compound sheet neither surface otw'hich is originally formed in contact'with the table. lt is well known that the table-surface of a glass sheet is inferior to the other surface, and by the inversion of the rst layer I obtain a sheet both surfaces of which have the gloss' and finish which or- I claimdinarily belongs to the upper surface only of a rolled or pressed sheet.

1` VThe method herein describedpf making f glass sheets which consists in rolling a sheet between the pressurein successivelyformed layers and then sub- 'jectingf the compound sheet topressure acting upon the entire crosssection kor 'the plate pplying surfaces 5 substantially asy described.

2. rDie method. herein described ofmaking sheetfglass, which consists 1n forming a sheet 0r Vlayer of glass, inverting it,.then forming thereon a second layer and thenpressing the surface'of thecompound sheet thus formed.

glass sheets whichconsists in rollinga sheet in successive formed layers and then forming thereon a figured surface by ressure applied to the entire cross-section .o thatfportion of of theplate to be figured; substantially as described.

- 4. The method herein described of making l glass sheets/.which consists in forming a sheet vor layer of glass, inverting it and then forming a second layer of glass thereon, bo'thsurfaces lor the compound sheet thus yformed lhaving a similar gloss or nishgsub'stantially' asdescribed.

In testimonywhereof have hereuntoset FRANK L. o. wADsw'oirrH'.v Witnesses) LINDSAYI PEDDiooizD, y

r` p N. M GRIFFIN. 

